Two-celled Life

The theory of evolution claims that life formed as single celled organisms and then gradually evolved to more complex forms. Why, then, are there no organisms, fossilized or living, that consist of 2, 3, 4 or 5 cells? Further, forms of life that consist of 6-20 cells are all parasites. Parasites are not able to survive on their own. They must have a host to support them. If macroevolution happened, we should find many transistional forms of life with 2-20 cells. We don't. This is yet another example of the fact that evolution does not answer the questions about the origin of life; it only raises more questions.